So, everyone knows that Mars is really far away, right? Right now, it takes months to travel the vast distance, but one scientist thinks there is a way to cut that down to half an hour. This wild idea belongs to Philip Lubin, a researcher at the University of California at Santa Barbara’s Experimental Cosmology Group. His theory involves firing a laser at a tiny unmanned spacecraft to help it achieve much faster travel speeds, but there’s a lot more to the story. The current concepts for interstellar travel at insane speeds don’t include any plans to stop.
The concept of using laser propulsion to speed up interstellar travel emerged last year as Lubin worked on NASA’s Innovative Advanced Concepts (NIAC) program. He suggests that a tiny unmanned spacecraft with a one-meter laser sail, which he named DE-STAR (Directed Energy System for Targeting of Asteroids and ExplorRation), could be propelled by aiming a powerful laser at its sail while still in Earth orbit. Doing so, Lubin believes, would accelerate the craft to a significant fraction of the speed of light.
Lubin’s theory starts with cutting down the time it takes to travel the equivalent distance to Mars to a few days, down from several months, but he thinks it may be possible to refine the technology and eventually reduce that time to 30 minutes. “As an example, on the eventual upper end, a full scale DE-STAR 4 (50-70 GW) will propel a wafer scale spacecraft with a one meter laser sail to about 26 percent the speed of light in about 10 minutes, reach Mars (1 AU [astronomical unit, the Earth-Sun distance]) in 30 minutes, pass Voyager 1 in less than 3 days, pass 1,000 AU in 12 days and reach Alpha Centauri in about 15 years,” Lubin wrote in a paper titled “A Roadmap to Interstellar Flight,” which was published last year.
Inhabitat contacted Lubin for further clarification. He says that, because the laser propulsion system described here doesn’t have brakes, there would need to be another way to make the craft stop. “This could be in the form of an ion engine that we power remotely from the main laser on the Earth (this is what we refer to as a beamed power mode) or could be chemical in nature, ” Lubin told Inhabitat. “But if chemical, you will typically need a lot of chemical propellant. The other option is to carry an eject-able mirror that shines light back from the Earth based laser somewhat like the reverse thruster on a jet after landing.”
So, there are some of the possibilities that researchers are looking into for the long-term applications of laser-propelled interstellar flight. Another option, Lubin says, is to build another laser in orbit around the desired destination, “and then ‘ping-pong’ the spacecraft” in order to make it possible for it to land, whether that’s on Mars or on another planet. Although this is a possibility, it’s a bit far-fetched at the moment because the construction of a second laser system would be an enormous project, to say the least.
Via IFL Science
Image via NASA